The proposed research will investigate variables influencing the psychosocial development of nonhuman primates. Two projects are described, both focusing on maternal influences on the developing monkey. The initial project, now in progress, places primary emphasis on systematic analysis of social, emotional and cognitive consequences for the infant macaque of variations in maternal attributes. Completion of this work is one of the objectives of the proposed research. The second project will investigate the causes, forms, and consequences of mother-infant conflict. Reliable and sensitive methods for identifying, ordering, and analyzing conflictual transactions between mother and infant will be developed, and data will be secured on mother-infant conflict in various species and situations. The long-range developmental consequences of different kinds and amounts of mother-infant conflict will be determined. The common goal of both projects is a fuller understanding of basic developmental processes with particular reference to the social behavior of the immature and adult primate.